Test triggered circuit breaker during multisearch (#3076)

elastic4s-tests/src/test/scala/com/sksamuel/elastic4s/search/MultiSearchCircuitBreakerTest.scala

@@ -0,0 +1,37 @@
+package com.sksamuel.elastic4s.search
+
+import scala.util.Try
+
+import com.sksamuel.elastic4s.testkit.DockerTests
+import org.scalatest.BeforeAndAfterAll
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.should.Matchers
+
+class MultiSearchCircuitBreakerTest
+  extends AnyFlatSpec
+    with DockerTests
+    with Matchers
+    with BeforeAndAfterAll {
+
+  override def beforeAll(): Unit =
+    Try {
+      client.execute {
+        clusterTransientSettings(Map("indices.breaker.total.limit" -> "1b"))
+      }.await
+    }
+
+  "a multi search request" should "return an error when the circuit breaker is triggered" in {
+    val request = multi(search("_all"))
+    val response = client.execute(request).await
+    response.isError shouldBe true
+    response.status shouldEqual 429
+    response.error.`type` shouldBe "circuit_breaking_exception"
+  }
+
+  override def afterAll(): Unit =
+    Try {
+      client.execute {
+        clusterTransientSettings(Map("indices.breaker.total.limit" -> null))
+      }.await
+    }
+}